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Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems
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作者 Sabrina Meddah Sid Ahmed Tadjer +3 位作者 Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche 《Structural Durability & Health Monitoring》 EI 2025年第1期77-103,共27页
Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emp... Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry. 展开更多
关键词 Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis field data analysis
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Research status and prospects of the fractal analysis of metal material surfaces and interfaces
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作者 Qinjin Dai Xuefeng Liu +2 位作者 Xin Ma Shaojie Tian Qinghe Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期20-38,共19页
As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal... As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal materials at various scales and dimensions.Conventional methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and interfaces.However,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal materials.From the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear surfaces.The relationship between the fractal dimensions and properties of metal material surfaces and interfaces is summarized.Starting from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be developed.It is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future. 展开更多
关键词 metal material surfaces and interfaces fractal analysis fractal dimension HOMOGENEITY
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Antioxidant and lipoxygenase inhibitory properties of a novel flavonoid from Pistacia chinensis Bunge and its molecular docking analysis
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作者 Abdur Rauf Zuneera Akram +6 位作者 Naveed Muhammad Najla AlMasoud Taghrid Saad Alomar Saima Naz Abdul Wadood Chandni Hayat Marcello Iriti 《Traditional Medicine Research》 2025年第2期30-36,共7页
Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and ... Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and anti-lipoxygenase(LOX)properties of the isolated compound 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-one from Pistacia chinensis.Methods:LOX assay and antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl(DPPH)assay were performed.Molecular docking studies were conducted using a molecular operating environment.Results:The LOX assay revealed significant inhibitory effects at 0.2µM concentration,with an IC50 value of 37.80µM.The antioxidant effect demonstrated dose-dependency across 5 to 100µg/mL concentrations,reaching 93.09%at 100µg/mL,comparable to ascorbic acid’s 95.43%effect.Molecular docking studies highlighted strong interactions with the lipoxygenase enzyme,presenting an excellent docking score of-10.98 kcal/mol.Conclusion:These findings provide valuable insights into Pistacia chinensis’chemical components and biological effects,reinforcing its traditional medicinal applications. 展开更多
关键词 Pistacia chinensis Bunge ANTIOXIDANT DPPH assay antilipoxygenase docking analysis
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Prenatal ultrasonography and genetic analysis of fetal cleidocranial dysplasia:A case report
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作者 Feng Wang Pei-Feng Dai Wen-Juan Gao 《World Journal of Clinical Cases》 SCIE 2025年第10期28-34,共7页
BACKGROUND Cleidocranial dysplasia(CCD)is an infrequent clinical condition with an autosomal dominant inheritance pattern.It is characterized by abnormal clavicles,patent sutures and fontanelles,supernumerary teeth,an... BACKGROUND Cleidocranial dysplasia(CCD)is an infrequent clinical condition with an autosomal dominant inheritance pattern.It is characterized by abnormal clavicles,patent sutures and fontanelles,supernumerary teeth,and short stature.Approximately 60%-70%of patients with CCD have mutations in the RUNX family transcription factor 2 gene.However,prenatal diagnosis of CCD is difficult when the family history is unknown.CASE SUMMARY We report a rare case of fetal CCD with an unknown family history,confirmed by prenatal ultrasonography and genetic testing at a gestational age of 16 weeks.The genetic reports indicated that the fetus carried pathogenic mutations in the RUNX family transcription factor 2 gene(c.674G>A).After careful consideration,the pregnant woman and her family decided to continue the pregnancy.CONCLUSION Definitive prenatal diagnosis of CCD should include family history,ultrasound diagnosis,and genetic analysis,especially if family history is unknown. 展开更多
关键词 Cleidocranial dysplasia Genetic analysis Ultrasonic diagnosis PRENATAL Case report
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Retrospective analysis of pathological types and imaging features in pancreatic cancer: A comprehensive study
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作者 Yang-Gang Luo Mei Wu Hong-Guang Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期121-129,共9页
BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features ... BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features is crucial for early detection and appropriate treatment planning.AIM To retrospectively analyze the relationship between different pathological types of pancreatic cancer and their corresponding imaging features.METHODS We retrospectively analyzed the data of 500 patients diagnosed with pancreatic cancer between January 2010 and December 2020 at our institution.Pathological types were determined by histopathological examination of the surgical spe-cimens or biopsy samples.The imaging features were assessed using computed tomography,magnetic resonance imaging,and endoscopic ultrasound.Statistical analyses were performed to identify significant associations between pathological types and specific imaging characteristics.RESULTS There were 320(64%)cases of pancreatic ductal adenocarcinoma,75(15%)of intraductal papillary mucinous neoplasms,50(10%)of neuroendocrine tumors,and 55(11%)of other rare types.Distinct imaging features were identified in each pathological type.Pancreatic ductal adenocarcinoma typically presents as a hypodense mass with poorly defined borders on computed tomography,whereas intraductal papillary mucinous neoplasms present as characteristic cystic lesions with mural nodules.Neuroendocrine tumors often appear as hypervascular lesions in contrast-enhanced imaging.Statistical analysis revealed significant correlations between specific imaging features and pathological types(P<0.001).CONCLUSION This study demonstrated a strong association between the pathological types of pancreatic cancer and imaging features.These findings can enhance the accuracy of noninvasive diagnosis and guide personalized treatment approaches. 展开更多
关键词 Pancreatic cancer Pathological types Imaging features Retrospective analysis Diagnostic accuracy
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Comprehensive bibliometric analysis of pharmacotherapy for bipolar disorders:Present trends and future directions
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作者 Bo-Fan Chen Li Liu +13 位作者 Fang-Zhen Lin Hai-Min Zeng Hai-Qiang Huang Chun-Fang Zhang Cong-Cong Liu Xiang Chen Jie Peng Yun-Fa Wang Zhi-Lin Wang Bin Chen De-Le Liu Yun Liu Zheng-Zheng Li Xin-Xing Zeng 《World Journal of Psychiatry》 SCIE 2025年第1期153-167,共15页
BACKGROUND Bipolar disorder(BD)is a severe mental illness characterized by significant mood swings.Effective drug treatment modalities are crucial for managing BD.AIM To analyze the current status and future trends of... BACKGROUND Bipolar disorder(BD)is a severe mental illness characterized by significant mood swings.Effective drug treatment modalities are crucial for managing BD.AIM To analyze the current status and future trends of global research on BD drug treatment over the last decade.METHODS The Web of Science Core Collection database spanning from 2015 to 2024 was utilized to retrieve literature related to BD drug treatment.A total of 2624 articles were extracted.Data visualization and analysis were conducted using CiteSpace,VOSviewer,Pajek,Scimago Graphica,and R-studio bibliometrix to identify RESULTS The United States,China,and the United Kingdom have made the most significant contributions to research on BD drug treatment and formed notable research collaboration networks.The University of Pittsburgh,Massachusetts General Hospital,and the University of Michigan have been identified as the major research institutions in this field.The Journal of Affective Disorders is the most influential journal.A keyword analysis revealed research hotspots related to clinical symptoms,drug efficacy,and genetic mechanisms.A citation analysis identified the management guidelines published by Yatham et al in 2018 as the most cited paper.CONCLUSION This study provides a detailed overview of the field of BD drug treatment,highlighting key contributors,research hotspots,and future directions.The study findings can be employed as a reference for future research and policymaking,which may enable further development and optimization of BD pharmacotherapy. 展开更多
关键词 Bipolar disorder Drug treatment Bibliometric analysis VISUALIZATION Mental disorder
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Targeted gene sequencing and bioinformatics analysis of patients with gallbladder neuroendocrine carcinoma:A case report
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作者 Yun-Chuan Yang Zhi-Tao Chen +2 位作者 Da-Long Wan Hui Tang Mu-Lin Liu 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期239-251,共13页
BACKGROUND Gallbladder neuroendocrine carcinoma(NEC)represents a subtype of gallbladder malignancies characterized by a low incidence,aggressive nature,and poor prognosis.Despite its clinical severity,the genetic alte... BACKGROUND Gallbladder neuroendocrine carcinoma(NEC)represents a subtype of gallbladder malignancies characterized by a low incidence,aggressive nature,and poor prognosis.Despite its clinical severity,the genetic alterations,mechanisms,and signaling pathways underlying gallbladder NEC remain unclear.CASE SUMMARY This case study presents a rare instance of primary gallbladder NEC in a 73-year-old female patient,who underwent a radical cholecystectomy with hepatic hilar lymphadenectomy and resection of liver segments IV-B and V.Targeted gene sequencing and bioinformatics analysis tools,including STRING,GeneMANIA,Metascape,TRRUST,Sangerbox,cBioPortal and GSCA,were used to analyze the biological functions and features of mutated genes in gallbladder NEC.Twelve mutations(APC,ARID2,IFNA6,KEAP1,RB1,SMAD4,TP53,BTK,GATA1,GNAS,and PRDM3)were identified,and the tumor mutation burden was determined to be 9.52 muts/Mb via targeted gene sequencing.A protein-protein interaction network showed significant interactions among the twelve mutated genes.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were used to assess mutation functions and pathways.The results revealed 40 tumor-related pathways.A key regulatory factor for gallbladder NEC-related genes was identified,and its biological functions and features were compared with those of gallbladder carcinoma.CONCLUSION Gallbladder NEC requires standardized treatment.Comparisons with other gallbladder carcinomas revealed clinical phenotypes,molecular alterations,functional characteristics,and enriched pathways. 展开更多
关键词 Gallbladder neuroendocrine carcinoma Targeted-gene sequencing Bioinformatics analysis case report IMMUNOCYTOCHEMISTRY Case report
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Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury
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作者 Xizi Song Ruixin Li +6 位作者 Xiaolei Chu Qi Li Ruihua Li Qingwen Li Kai-Yu Tong Xiaosong Gu Dong Ming 《Neural Regeneration Research》 SCIE CAS 2025年第10期2807-2822,共16页
Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes... Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target organs.This has led to restrictions on current therapeutic approaches.In this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target organs.After peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal cord.The nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury site.Corresponding damage to target organs can occur,including skeletal muscle atrophy and sensory receptor disruption.We then provide a brief review of the research advances in therapeutic approaches to peripheral nerve injury.The main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical exercise.However,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ pathway.Therefore,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery. 展开更多
关键词 central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach
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RAPD analysis of genetic diversity of nine strains of Auricularia auricular cultivated in Heilongjiang Province 被引量:7
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作者 李玲 李杰 +3 位作者 邹丽 白素英 牛黎明 马玉堃 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期136-138,共3页
Polymorphism of nine strains (CF05, CF09, 29, 916, AU9, Chang10, Chang7, 8808 and AU. Japanese) of A. auricular cultivated in Heilongjiang Province were analyzed by RAPD (Random Amplication polymorphic DNA). Thirt... Polymorphism of nine strains (CF05, CF09, 29, 916, AU9, Chang10, Chang7, 8808 and AU. Japanese) of A. auricular cultivated in Heilongjiang Province were analyzed by RAPD (Random Amplication polymorphic DNA). Thirteen primers were selected from forty PCR primers with 10bp long random primer. The results showed that nine strains of A. auricular have a high level of genetic diversity and the percentage of DNA polymorphic was 96.05. The genotypes of 9 strains of Auricularia auricular were identified by the fingerprints from primer 27 and primer 46 by RAPD analysis. The results are helpful for quickly identifying strains of A. auricular in its early breeding time, and also provides a powerful theoretic basis to differentiate strains (Auricularia auricular) whose morphology is very similar in breeding programs of edible fungus. 展开更多
关键词 Auricularia auricular rapd analysis DNA fingerprint Genetic diversity
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Genetic Diversity in Main Cultivars of Safflower in Xinjiang Uighur Autonomous Region Based on RAPD Analysis 被引量:11
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作者 岳庆妮 葛娟 +3 位作者 王蕾 张霞 王绍明 王建明 《Agricultural Science & Technology》 CAS 2008年第4期34-38,共5页
[Objective] Study on the genetic diversity in main cultivars of safflower distributing in Xinjiang Uighur Autonomous Region by means of RAPD makers.[Method] Genomic DNAs of 29 safflower accessions from Xinjiang Uighur... [Objective] Study on the genetic diversity in main cultivars of safflower distributing in Xinjiang Uighur Autonomous Region by means of RAPD makers.[Method] Genomic DNAs of 29 safflower accessions from Xinjiang Uighur Autonomous Region were extracted for PCR amplification using 20 RAPD primers.[Result] Totally 156 bands were amplified,among which 144 bands were polymorphic(accounting for 92.31%),indicating that safflower is endowed with plentiful genetic diversity.Based on the DNA fingerprint,the 29 safflower accessions were grouped into four populations,the classification results may be not related with ecological regionality.[Conclusion] RAPD technique is an available tool to analyze the genetic diversity of safflower germplasm at molecular level. 展开更多
关键词 SAFFLOWER GENETIC diversity rapd Cluster analysis
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RAPD Analysis of 33 Varieties of Banana 被引量:17
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作者 杜道林 苏杰 +3 位作者 周鹏 郑学勤 黄秉智 李丰年 《Acta Botanica Sinica》 CSCD 2001年第10期1036-1042,共7页
RAPD assessment of genetic variations in 33 varieties of banana (Musa nana Lour.) was carried out. Eighteen primers were screened from 249 10 bp arbitrary primers, and a total of 192 DNA bands were amplified, among wh... RAPD assessment of genetic variations in 33 varieties of banana (Musa nana Lour.) was carried out. Eighteen primers were screened from 249 10 bp arbitrary primers, and a total of 192 DNA bands were amplified, among which 183 (95.31%) were polymorphic. The average number of DNA bands amplified by each primer was 10.67, and the average genetic distance among 33 varieties was 0.3412. Based on UPGMA cluster analysis of 192 DNA bands amplified by 18 primers a DNA molecular dendrogram was established for 33 varieties of banana in China, which divided the 33 varieties into four groups: group A, B, C and D. Group A included 20 varieties, group B included 5 varieties, group C included 2 varieties and group D included 6 varieties. Group A could be divided into 3 sub-groups: A1, A2 and A3. The molecular foundation of genetic diversity of banana was also explored. 展开更多
关键词 BANANA VARIETY rapd genetic diversity
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Analysis of Genetic Structure of Natural Populations of Castanopsis fargesii by RAPDs 被引量:12
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作者 朱其慧 潘惠新 +3 位作者 诸葛强 尹佟明 邹惠渝 黄敏仁 《Acta Botanica Sinica》 CSCD 2002年第11期1321-1326,共6页
Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with ... Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with 41 oligonucleotide primers, out of which 157 loci were polymorphic and accounted for 40.78% of total genetic diversity at species level. Shannon's indices of diversity (I) and Nei's gene diversity ( h) were 0.459 7 and 0.296 at the species level, respectively. The result showed that genetic variation of C. fargesii populations mainly existed within populations. Genetic differentiation (Hsp-hpop)/Hsp estimated with Shannon's index of diversity and coefficient of gene differentiation (Gst) were 0.047 6 and 0.042 9 respectively, which were confirmed by the analysis of molecular variance (AMOVA). Therefore, it is apparent that within-population variation accounted for 94.97% and among-populations variation accounted for only 5.03% of the total genetic diversity. AMOVA also indicated that there was significant differentiation among populations as well as among individuals within a population. 展开更多
关键词 Castanopsis fargesii natural populations rapd genetic structure
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Genetic Diversity in Wild Grapes Native to China Based on Randomly Amplified Polymorphic DNA (RAPD) Analysis 被引量:29
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作者 罗素兰 贺普超 +1 位作者 郑学勤 周鹏 《Acta Botanica Sinica》 CSCD 2001年第2期158-163,共6页
The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one str... The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one strain of V. riparia L. Genetic diversity among these grapes was investigated based on RAPD analysis. The screening of 280 decamer oligonucleotides allowed the selection of 20 primers used for the analysis. A total of 191 RAPD markers were produced from the 20 selected primers. Relationships among the 83 clones or accessions based on their genetic distances were clustered using unweighted pair_group method arithmetic average (UPGMA) analysis in a dendrogram. Twenty_two clusters which fortunately adapted to 22 grape species level were clearly resolved on the dendrogram. The 18 wild grape species native to China were grouped into ten subclusters. The largest distance was found between V. riparia L., V. vinifera L., interspecific hybrid ( V. vinifera L.× V. larbrusca L.) and the wild grapes native to China. Among the wild grapes native to China, the largest distance was found between V. hancockii Hance and the other wild species. V. qinlingensis P.C.He was the second. Large genetic variation occurred among the different flower_type clones in one species. 展开更多
关键词 the wild grapes native to China VITIS genetic distance rapd
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RAPD Analysis for Genetic Diversity of Nineteen Common and Tartary Buckwheat Varieties 被引量:9
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作者 邓琳琼 张奎 +1 位作者 黄凯丰 陈庆富 《Agricultural Science & Technology》 CAS 2011年第1期65-69,共5页
[Objective]The study aimed to carry out RAPD analysis of genetic diversity of common and tartary buckwheat varieties.[Method] The genetic diversity of 19 common and tartary buckwheat varieties including the tested var... [Objective]The study aimed to carry out RAPD analysis of genetic diversity of common and tartary buckwheat varieties.[Method] The genetic diversity of 19 common and tartary buckwheat varieties including the tested varieties in Guizhou region during 1999-2010 and their parents were studied using 7 primers by means of random amplified polymorphic DNA(RAPD).[Result]A total of 149 DNA bands were obtained.In which,141 bands were polymorphic,accounting for 94.89%.Polymorphism analysis and cluster analysis showed that all varieties had their own special bands different from each other.The varieties native to Weining were close to each other,and other common buckwheat varieties were obviously different from each other.The interspecific genetic variation was the greatest;the intraspecific genetic variation of common buckwheat varieties was greater than that of tartary buckwheat varieties.[Conclusion]The RAPD fingerprints of the 19 buckwheat varieties were established in present study. 展开更多
关键词 Common buckwheat Tartary buckwheat rapd Genetic diversity
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RAPD Analysis for Genetic Diversity of Varanus salvator 被引量:1
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作者 傅美兰 于冬梅 +1 位作者 王莹 彭建军 《Agricultural Science & Technology》 CAS 2011年第3期400-404,共5页
[Objective] The aim was to carry out RAPD analysis on genetic diversity of Varanus salvator. [Method] 20 random primers were used for PCR amplification of genomic DNA of 36 individuals of V. salvator. [Result] 10 prim... [Objective] The aim was to carry out RAPD analysis on genetic diversity of Varanus salvator. [Method] 20 random primers were used for PCR amplification of genomic DNA of 36 individuals of V. salvator. [Result] 10 primers could produce highly reproducible RAPD bands. A total of 2 952 DNA fragments were successfully amplified. Each individual got 82 amplified bands on average,47 of which showed polymorphism. The polymorphic locus percent was 57.32%. The genetic distance among 36 individuals ranged from 0.035 9 to 0.335 9 with an average of 0.135 9. The Nei's gene diversity index (H) and Shannon's information index (I) were 0.181 9 and 0.263 0,respectively,indicating that V. salvator had greater genetic diversity. [Conclusion] The phylogenetic tree was inferred by using UPGMA analysis,it was found that the 36 individuals could be classified as one group,and there was no obvious population differentiation. 展开更多
关键词 Varanus salvator Genetic diversity rapd UPGMA analysis
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RAPD Analysis of Litchi chinensis Sonn.from Different Origins of China 被引量:2
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作者 梅志强 李春红 龚舒 《Agricultural Science & Technology》 CAS 2012年第1期64-67,共4页
[Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins.... [Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins. [Method] 5 Litchi cultivars from Sichuan, Guangxi, Guangdong, Fujian and Hainan were used as experimental materials to extract genomic DNA by modified CTAB method. Twenty primers with well reproducibility were randomly selected to conduct RAPD amplification to analyze the polymorphism and genetic relationship of the five cultivars. [Result] The polymor- phism of the five Litchi cultivars was 61%, with the similarity coefficient of 0.571 4- 0.803 6. The similarity coefficient of those from Guangdong and Guangxi was the largest of 0.803 6, and from Sichuan and Hainan was the lowest of 0.571 4. The resolution and production of RAPD was significantly improved by appropriately pro- longing the ramp time from annealing to extension to 0.3℃/s. [Conclusion] This study provided theoretical basis for the classification and breeding of Litchi. 展开更多
关键词 rapd RAMP LITCHI ORIGIN
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RAPD Analysis of Micropterus salmoides and Tilapia nilotica 被引量:3
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作者 张金洲 项智锋 谢红兵 《Agricultural Science & Technology》 CAS 2009年第6期37-39,共3页
The intra-population phylogenetic relationship between Micropterus salmoides and Tilapia nilotica was analyzed by random amplified polymorphic DNA ( RAPD) technique. The results showed that the similar coefficient o... The intra-population phylogenetic relationship between Micropterus salmoides and Tilapia nilotica was analyzed by random amplified polymorphic DNA ( RAPD) technique. The results showed that the similar coefficient of bands between M. salmoides and T. nilotica was 0.236, and the genetic distance was 0. 764, which indicated that M. salmoides had a distant relationship with T. nilotica. 展开更多
关键词 rapd Micropterus salmoides Tilapia nilotica Genetic distance
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Error Analysis and Compensation of Strapdown Inertial Navigation System 被引量:16
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作者 刘勤 刘莉 祁载康 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期117-120,共4页
Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy... Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy (defined by circular error probability), the types of appropriate sensors are chosen. The inertial measurement unit (IMU) is composed of those sensors. It is necessary to calibrate the sensors to obtain their error model coefficients of IMU. After calibration tests, the accuracy is calculated by uniform design method and it is proved that the accuracy of IMU is satisfied for the desired goal. 展开更多
关键词 error analysis strapdown inertial navigation system uniform design method calibration test
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RAPD analysis between color-different crab individuals of Portunus trituberculatus
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作者 迟大利 阎斌伦 +1 位作者 沈颂东 高焕 《Marine Science Bulletin》 CAS 2010年第2期47-54,共8页
The blue swimming crabs Portunus trituberculatus with tea-green and/or purple carapace color have been discovered on the shore of eastern part of China these days, In this paper, 40 color-different crab individuals we... The blue swimming crabs Portunus trituberculatus with tea-green and/or purple carapace color have been discovered on the shore of eastern part of China these days, In this paper, 40 color-different crab individuals were evaluated using 80 RAPD primers. 30 primers were selected using bulk segregation analysis (BSA) and RAPD-PCR analysis. The results showed that the ratio of polymorphic loci was 61.29%, and Nei's gene diversity was 0.375 6, and Shannon's information index was 0.554 5 among purple crab individuals; and the ratio of polymorphic loci was 62.44%, and Nei's gene diversity was 0.3451, and Shannon's information index was 0.5099 among tea-green crab individuals. It was clear that the genetic diversity between purple and tea-green crabs was similar, which indicated close phylogenetic relationships between the purple and tea-green crabs. In addition, two primers (SBS A09 and SBS G16) got specific DNA bands by comparing forty individuals of color-different crab individuals through RAPD-PCR analysis and the following electrophoresis. They indicated close phylogenetic relationships between purple and tea-green crabs. 展开更多
关键词 body-color phylogenetic relationships Portunus trituberculatus rapd
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Effect of BSA on RAPD Analysis of Cynomorium songaricum
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作者 周玉碧 叶润蓉 +2 位作者 卢学峰 刘洋 彭敏 《Agricultural Science & Technology》 CAS 2007年第3期64-67,共4页
[Objective] The objective of the study was to study the role played by BSA in Random Amplified polymorphic DNA(RAPD).[Method]The improvement of RAPD amplification was observed by adding BSA in the analysis of Cynomori... [Objective] The objective of the study was to study the role played by BSA in Random Amplified polymorphic DNA(RAPD).[Method]The improvement of RAPD amplification was observed by adding BSA in the analysis of Cynomorium songaricum RAPD.[Result] The result showed that in the process of Cynomorium songaricum RAPD analysis,the effect of amplification improved significantly and the dosage of Taq enzyme declined by adding BSA.The suitable concentration of BSA used in RAPD of Cynomorium songaricum Rupr was 2 μg/μl.[Conclusion]It is feasible to add BSA to improve the RAPD analysis of plants.This study has provided foundation for the application of BSA in RAPD analysis. 展开更多
关键词 BSA Cynomorium songaricum rapd
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